This invention relates generally to a photographic camera with shock inhibiting means, and more particularly, to a photographic camera having a shock inhibiting means for positively inhibiting the opening of an automatic shutter blade mechanism through extraneous or sudden shock.
Electrically driven exposure control systems are advantageous in that they minimize operator requirements of shutter recocking, etc. and are particularly suited for electronic control. For conservation of power, such systems require provision of a stable deenergized shutter condition when the camera is not undergoing exposure operations. An exemplary system of this type is described in U.S. Pat. No. 3,820,128 issued to J. P. Burgarella, et al on June 25, 1974 wherein a compact, automated single lens reflex camera is described, and which includes a shutter diaphragm system having shutter blades mechanically biased to an open (viewing) position and electrically biased to a closed position. Advantageously, the exposure system of the above-noted patent is electrically sequenced to provide a precise control over the exposure operation. That is, both the initiation and termination of the exposure interval are electrically, rather than mechanically, determined and, accordingly, may be precisely controlled. However, while the system is particularly adapted for through the lens viewing and provides a normally open shutter, it can be understood that it would also be desirable to provide a normally closed arrangement without compromising the system advantages.
Toward this end, an exposure control system utilizing electrically controlled shutter blade elements employing a latch for holding the blades in a light blocking position is provided as more fully described in a copending application for U.S. Patent Ser. No. 608,663, entitled "Electro-Mechanical Shutter System Having Mechanical Latch, " by L. Douglas, filed Aug. 8, 1975. In accordance with the general concept of the aforementioned invention, the exposure control system includes a reliable shutter latching arrangement which requires shutter actuation for release. Thus, the exposure control system includes a shutter latch released in response to combined electrical and mechanical actuation of the exposure control system. A mechanical shutter latch arrangement is unlocked just before or simultaneously with energization of the exposure control system and then subsequently released in response to initial shutter blade movement resulting from energization of the electrical drive element.
Another shutter latch arrangement providing for normally closed shutter blade elements is disclosed in a copending application for U.S. Pat. Ser. No. 648,725, entitled "Shutter Latch Arrangement Releasable Through Shutter Blade Actuation and Resettable Through Film Advancement," by G. D. Whiteside and B. K. Johnson filed Jan. 13, 1976. The shutter latch mechanism of this invention is released in response to initial shutter blade movement resulting from energization of the shutter drive means and thereafter moved into position to relatch the shutter blades in response to film advancement. Unlatching of the shutter blades also operates to simultaneously actuate a power interlock switch to maintain the electrical energization of a photographic exposure control system even after a user manually deactuates a shutter button. There is additionally provided a shock damping arrangement to deter the accidental unlatching of the shutter blade mechanism resulting from shutter blade movement occasioned through extraneous vibrations, sudden shock or otherwise. Despite this shock damping arrangement, there may nevertheless occur an accidental unlatching under severe or repeated shock. The problem may be particularly acute when the cameras are shipped from their place of manufacture, at which time there may be expected to occur severe shocks during transit.
Should the shutter become accidentally unlatched during shipment, then the power interlock switch will also become actuated as previously discussed so that subsequent insertion of a battery powered film cassette within the film receiving chamber of the camera will immediately cause the camera to commence an automatic film exposure and processing cycle even before the film loading access door to the camera can be closed by the camera operator. Whereas cameras of the aforementioned type additionally provide for an automatic film advancement operation, there may also occur an automatic advancement of the forwardmost film unit or so-called "dark slide" from the camera before the camera operator can even close the camera film loading access door thereby resulting in the exiting film unit jamming the closing film access door.
Therefore it is a primary object of this invention to provide an improved shock inhibiting means for positively inhibiting the opening of an automatic shutter latch mechanism despite severe or repeated shock which might cause the shutter latch mechanism to unlatch despite the aforementioned shock damping arrangement.
Other objects of the invention will in part be obvious and will in part appear hereinafter.